Age: 15 Height: 159 cm
Kou is one of Hiyori's classmates in her second year, and sits beside her in class. He has a similar personality and height with her, causing him to be constantly teased with Hiyori during his first year. When he first met Hiyori, he disliked her because he thought that she had a calculating personality, and believed that Hiyori was an attention-seeking girl. He eventually becomes one of Hiyori's good friends. He also does not enjoy school trips. He later meets Ri-chan, Hiyori's best friend and finds her weird and notice that she eats a lot. Hiyori thinks that Kou and Ri chan would look good as a couple.